The literature describes many ways of preparing gabapentin from a variety of starting materials, as the hydrochloride hydrate, the monohydrate and the sodium salt forms. However, the prior art neither discloses nor suggests the preparation of gabapentin tannate. The formation of a tannate salt of gabapentin is unexpected because of the close proximity of a carboxylic acid group to the amine group. The negative charge on the carboxylic acid group was expected to shield and possibly neutralize the positive charge on the proximal nitrogen. Since tannate salts are thought to normally form through an ionic interaction with a positively charged amine functional group, the close proximity of the carboxylic acid group was expected to prevent the formation of the tannate salt. Further, none of these references mention the preparation and incorporation of gabapentin tannate into suitable dosage forms for pharmaceutical use.